Thanks for working on this.
On Wed, Sep 25, 2019 at 6:10 PM Stephen Hemminger
<step...@networkplumber.org> wrote:
>
> The internal structure of lcore_config is no longer be part of
> visible API/ABI. Make it private to EAL.
>
> Rearrange and resize the fields in the structure so it takes
> less memory (and cache footprint).
This patch is missing the release notes update.
>
> Signed-off-by: Stephen Hemminger <step...@networkplumber.org>
> ---
> v7 - add eal_private.h to windows
>
> lib/librte_eal/common/eal_common_launch.c | 2 ++
> lib/librte_eal/common/eal_private.h | 22 +++++++++++++++++++++
> lib/librte_eal/common/include/rte_lcore.h | 24 -----------------------
> lib/librte_eal/common/rte_service.c | 2 ++
> lib/librte_eal/rte_eal_version.map | 1 -
> lib/librte_eal/windows/eal/eal_thread.c | 1 +
> 6 files changed, 27 insertions(+), 25 deletions(-)
>
> diff --git a/lib/librte_eal/common/eal_common_launch.c
> b/lib/librte_eal/common/eal_common_launch.c
> index fe0ba3f0d617..cf52d717f68e 100644
> --- a/lib/librte_eal/common/eal_common_launch.c
> +++ b/lib/librte_eal/common/eal_common_launch.c
> @@ -15,6 +15,8 @@
> #include <rte_per_lcore.h>
> #include <rte_lcore.h>
>
> +#include "eal_private.h"
> +
> /*
> * Wait until a lcore finished its job.
> */
> diff --git a/lib/librte_eal/common/eal_private.h
> b/lib/librte_eal/common/eal_private.h
> index 798ede553b21..25e80547904f 100644
> --- a/lib/librte_eal/common/eal_private.h
> +++ b/lib/librte_eal/common/eal_private.h
> @@ -10,6 +10,28 @@
> #include <stdio.h>
>
> #include <rte_dev.h>
> +#include <rte_lcore.h>
> +
> +/**
> + * Structure storing internal configuration (per-lcore)
> + */
> +struct lcore_config {
> + uint32_t core_id; /**< core number on socket for this lcore */
> + uint32_t core_index; /**< relative index, starting from 0 */
> + uint16_t socket_id; /**< physical socket id for this lcore */
> + uint8_t core_role; /**< role of core eg: OFF, RTE, SERVICE */
> + uint8_t detected; /**< true if lcore was detected */
> + volatile enum rte_lcore_state_t state; /**< lcore state */
> + rte_cpuset_t cpuset; /**< cpu set which the lcore affinity to */
> + pthread_t thread_id; /**< pthread identifier */
> + int pipe_master2slave[2]; /**< communication pipe with master */
> + int pipe_slave2master[2]; /**< communication pipe with master */
> + lcore_function_t * volatile f; /**< function to call */
> + void * volatile arg; /**< argument of function */
> + volatile int ret; /**< return value of function */
> +};
> +
> +extern struct lcore_config lcore_config[RTE_MAX_LCORE];
Everything but cpuset can fit in a cache line.
You could just move the cpuset field at the end of the structure and
change detected to uint8_t.
This gives the following layout:
struct lcore_config {
pthread_t thread_id; /* 0 8 */
int pipe_master2slave[2]; /* 8 8 */
int pipe_slave2master[2]; /* 16 8 */
volatile lcore_function_t * f; /* 24 8 */
volatile void * arg; /* 32 8 */
volatile int ret; /* 40 4 */
volatile enum rte_lcore_state_t state; /* 44 4 */
unsigned int socket_id; /* 48 4 */
unsigned int core_id; /* 52 4 */
int core_index; /* 56 4 */
uint8_t detected; /* 60 1 */
uint8_t core_role; /* 61 1 */
/* XXX 2 bytes hole, try to pack */
/* --- cacheline 1 boundary (64 bytes) --- */
rte_cpuset_t cpuset; /* 64 128 */
/* --- cacheline 3 boundary (192 bytes) --- */
/* size: 192, cachelines: 3, members: 13 */
/* sum members: 190, holes: 1, sum holes: 2 */
};
The resulting structure is only two bytes bigger than your proposal
and does not touch existing integer types (avoiding the risk of some
integer conversion on socket_id for example).
--
David Marchand
